Turbines are widely used in a variety of aviation, industrial, and power generation applications to perform work. Each turbine generally includes alternating stages of circumferentially mounted stator vanes and rotating blades. Each stator vane and rotating blade may include high alloy steel and/or ceramic material shaped into an airfoil. A compressed working fluid, such as steam, combustion gases, or air, flows across the stator vanes and rotating blades along a gas path in the turbine. The stator vanes accelerate and direct the compressed working fluid onto the subsequent stage of rotating blades to impart motion to the rotating blades and perform work.
High temperatures associated with the compressed working fluid may lead to increased wear and/or damage to the stator vanes and/or rotating blades. As a result, a cooling media may be supplied inside the airfoils and released through the airfoils to provide film cooling to the outside of the airfoils. Trenches in the airfoils evenly distribute the cooling media across the external surface of the airfoils. However, an improved airfoil that varies the distribution of the cooling media across the external surface of the airfoils would be useful.